Among the various Vedic hymns recited daily by a Vaidika the Sata Rudriya occupies the prime place. Popularly known as Sri Rudram, this hymn of praise of, and prayer to the Lord is a part of Krsna Yajur Veda. Perhaps this hymn is the source of inspiration for the Namavalis consisting of one thousand and eight names revealing and praising the Lord invoked in a certain form.
In the epic Mahabharata, Bhisma gives the thousand names of Lord Visnu, known as Visnu Sahasranama.There are similar namavalis mentioned in the various Puranas. In both form and content, all of them are not different from the Rudram. Even in the Vedas, one does not see a section like this hymn consisting of so many names of the Lord along with the word, Namah,salutation.
The famous five syllabic mantra, Namah Sivaya,is from this great hymn.Sri Rudram is known as Rudropanishad. Though it forms part of Karma Kanda, it ranks with the Upanishads of the Gnana Kanda.It is one of the five scriptural texts chosen by the ancients for constant repetition and meditation.
Sri Rudram shows the way for this Upasana or Meditation through the three hundred Namaskaras.As by pouring water at the root of a tree, all its branches are nourished, by pleasing Sri Rudra, through Rudrajapa, all the Devas are pleased. One attains Bhukti and Mukti, enjoyment of life as well as freedom from the ills of the world by the chanting of Sri Rudram with devotion.
This is the best Prayaschittam, atonement for all sins and the foremost sadhana for attainment of cherished desires. Taittiriya Upanishad says, if one adores Iswara through repeated namaskaras, all the longings of the heart will be fulfilled and they will be at his feet. Sri Rudram shows the way for this Upasana through the three hundred namaskaras.
Salutations go to the Rudra who is all-pervasive and behind and beyond all forms of divinity; not only divinity but also all beings-human and sub-human. Rudra is in all these forms before us. The Sata Rudriya consists of eleven sections, anuvakas. Each anuvaka has a number of hymns in different Vedic meters. In the first nine sections of the Rudram, the word namah occurs three hundred times. And, therefore, the Sata Rudriya is also popular as Namakam in the south of India. This hymn is invariably followed by another hymn where the syllables ca and me occur in every sentence, and therefore, that hymn is called Camaka.